Super Tuesday: Amy Klobuchar and Pete Buttigieg endorse Joe Biden

Millions of voters from Maine to California headed to the polls on Super Tuesday, the delegate-rich prize in the fight for the Democratic presidential nomination that's shaping up as a contest between two starkly different visions for the party's future as it hurtles toward a November rematch with President Donald Trump.

Democrat Pete Buttigieg (R) endorsed Joe Biden for US president on March 2, 2020, providing a major boost to the former vice president's White House hopes just one day after the former Indiana mayor himself dropped out of the race.AFP

Joe Biden appeared to be surging ahead in the heated Democratic Party's presidential race with the ex-US vice president picking up three key endorsements from former rivals on the eve of the "Super Tuesday" primaries, the most important day in the race for the White House.

Millions of voters from Maine to California headed to the polls on Super Tuesday, the delegate-rich prize in the fight for the Democratic presidential nomination that's shaping up as a contest between two starkly different visions for the party's future as it hurtles toward a November rematch with President Donald Trump.

Vermont Sen. Bernie Sanders, who has energized liberals and young voters, sought to pull away from the rest of the field, while former vice president Joe Biden hoped to ride a wave of momentum and endorsements to cement himself as the standard-bearer for the party's moderate wing.

The two men, riding atop a rapidly shrinking Democratic field, have assembled coalitions of disparate demographics and political beliefs, and the day could help shape whether the nomination fight will stretch until the party's convention this summer in Milwaukee.

But the 14 coast-to-coast contests seemed certain to provide several other twists and turns, including the first test of billionaire Mike Bloomberg's massive spending in the Democratic race.